Patent US3239610A successfully refreshed from Google Patents.
US3239610A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Line circuit for key telephone system
Assignee: AT&T Inc
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Filing: 1962-12-26
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Granted: 1966-03-08
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Expires: 1982-12-26
Abstract
No abstract record available.
Inventors
- 👤 Charles E Morse
- 👤 John P Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:33
CPC Classifications
H; H04; H04M; H04M9/00; H04M9/002; H04M9/005; H04M9/006
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
75 words
IN A LINE CIRCUIT FOR A KEY TELEPHONE SYSTEM INCLUDING A SUBCRIBER''S TELEPHONE LINE, LOCAL RINGING MEANS, MEANS RESPONSVE TO RINGING CURRENT FROM A REMOTE LOCATION FOR INITIATING THE OPERATION OF SAID LOCAL RINGING MEANS, MEANS RESPONSIVE TO THE TERMINATION OF SAID RINGING CURRENT FOR DISABLING SAID LOCAL RINGING MEANS, AND MEANS FOR HOLDING SAID SUBSCRIBER''S LINE, SAID INITIATING MEANS AND SAID HOLDING MEANS EACH INCLUDING A COMMON MULTIFUNCTION RELAY AND A COMMON MULTIFUNCTION TRANSISTOR.
Claim 2
Dependent Claim
75 words
IN A LINE CIRCUIT FOR A KEY TELEPHONE SYSTEM INCLUDING A SUBCRIBER''S TELEPHONE LINE, LOCAL RINGING MEANS, MEANS RESPONSVE TO RINGING CURRENT FROM A REMOTE LOCATION FOR INITIATING THE OPERATION OF SAID LOCAL RINGING MEANS, MEANS RESPONSIVE TO THE TERMINATION OF SAID RINGING CURRENT FOR DISABLING SAID LOCAL RINGING MEANS, AND MEANS FOR HOLDING SAID SUBSCRIBER''S LINE, SAID INITIATING MEANS AND SAID HOLDING MEANS EACH INCLUDING A COMMON MULTIFUNCTION RELAY AND A COMMON MULTIFUNCTION TRANSISTOR.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-03-07 | 1969-09-06 | 1970-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-03-07 | 1973-09-06 | 1974-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-03-07 | 1977-09-06 | 1978-03-08 | $7700.00 | Window Closed / Lapsed |